Electrical connector

ABSTRACT

An electrical connector for connection to a lead wire comprising at least one terminal including a male or female contact portion at one end thereof, a resilient bellmouth-shaped portion interposed between the contact portion and the end of the terminal adapted for connection to the lead wire, and an engaging portion; and a connector body including a terminal-receiving aperture with its internal surface partly or wholly tapered and a portion for holding the terminal by engagement with the engaging portion of the terminal; the engaging portion of the terminal being inserted into the terminal-receiving aperture to such an extent as to engage with the holding portion, the bellmouthshaped portion of the terminal being resiliently pressed against the internal surface of the tapered portion thereby to support the electrical connector.

United StatesPatent Karube et al.

[ ELECTRICAL CONNECTOR [75] Inventors: Soichi Karube, Tokyo; YoshioHamada, Hitachi; Yoshiyasu Suganuma, Hiratsuka, all of Japan [73]Assignees: Kanto Seiki Co., Ltd., Saitama-ken;

Hitachi Cable Ltd., Tokyo; Nippon Tanshi, Ltd., Kanagawa-ken, Japan [22]Filed: May 30, 1972 [21] Appl. No.: 257,553

[30] Foreign Application Priority Data June 2, 1971 Japan 46/38751 June2, 1971 Japan 46/38752 [52] U.S. Cl 339/217 S, 339/252 P, 339/258 RR[51] Int. C1,. H01! 9/08 [58] Field of Search 339/217 R, 217 S, l339/221 R, 221 M, 256 R, 256 C, 256 A, 256 S, 256 SP, 256 T, 258 A, 258C, 258 R,

258 F, 258 P, 258 S, 258 T, 258 TC, 241,

252 R, 252 P, 253 R, 253 S [56] 1 References Cited UNITED STATES PATENTS3,178,673 4/1965 Krehbiel t. 339/217 S 3,543,226 11/1970 Laboue 339/176Jan. 1, 1974 3,588,789 6/1971v Kailus 339/217 S 3,474,398 10/1969Piorruneck 339/217 S 3,659,254 4/1972 Cartwright 339/221 R 2,359,63410/1944 Franklin 339/217 S Primary Examiner-Marvin A. Champion AssistantExaminer-Robert A. Hafer Attorney-Paul M. Craig, Jr. et a1.

[57] ABSTRACT An electrical connector for connection to a lead wirecomprising at least one terminal including a male or female contactportion at one end thereof, a resilient bellmouth-shaped portioninterposed between the contact portion and the end of the terminaladapted for connection to the lead wire, and an engaging portion; and aconnector body including a terminalreceiving aperture with its internalsurface partly or wholly tapered and a portion for holding the terminalby engagement with the engaging portion of the terminal; the engagingportion of the: terminal being inserted into the terminal-receivingaperture to such an extent as to engage with the holding portion, thebellmouth-shaped portion of the terminal being resiliently pressedagainst the internal surface of the tapered portion thereby to supportthe electrical connector.

5 Claims, 8 Drawing Figures ELECTRICAL CONNECTOR BACKGROUND OF THEINVENTION 1. Field of the Invention This invention relates toanadvantageous electrical Connector used as an internal wiring connnectingmeans for automotive vehicles or the like.

2. Description of the Prior Art The distribution lines called a wireharness for automotive electric systems generally consist of amultiplicity of lead wires each with a terminal, which are divided intoa plurality of batches each including about to lead wires. The terminalsof each batch of lead wires are contained in a single connector. Suchconnectors are adapted for male and female type of engagement toaccomplish the connection not only between lead wires themselves butalso between lead wires and external equipment. It is essential to thistype of connector that terminals are easily contained in the connectorbody, that thecontained terminals do not come off the connector body atthe time of connector engagement and disengagement, and that the centerline of each terminal is aligned with that of the mating terminal. Thethird requirement arises because it is usual that a plurality ofterminals are connected in a batch to a plurality of the matingterminals.

Especially, the above-mentioned second and third requirements areclosely related to the workability of connector engagement anddisengagement, and any connector which cannot meet these requirementshas little commercial value.

SUMMARY OF THE INVENTION An object of the invention is to provide anelectrical connector in which terminals are easily contained in theconnector body.

Another object of the invention is to provide an electrical connector inwhich the contained terminals are combined strongly with the connectorbody and maintain their center lines aligned.

The electrical connector according to the present invention which isintended to achieve the abovementioned objects comprises at least oneterminal and a connector body, the terminal including a male or femaleContact portion at one end thereof, a resilient bellmouth portion inmidway thereof and an resilient hook extending sideway from thesmall-diameter side of the bellmouth portion, said connector bodyincluding at least one terminal-receiving aperture with an internalsurface partially or wholly tapered and a holding portion at thesmallest-diameter side of said tapered portion; in which the terminal isinserted into the terminal-receiving aperture to such an extent that thehook which enters the aperture from the large-diameter side thereofpasses the smallest-diameter portion thereof, so that not only the hookis held by the holding-portion but also the bellmouth portion isresiliently pressed against the internal surface of the tapered portion.

In the electrical connector with the construction as described above,when the hook of the terminal inserted into the terminal-receivingaperture from the large-diameter side of the tapered portion thereofreaches the position past the smallest-diameter portion of the aperture,the hook automatically engages with the holding portion by restitution,and at the same time the bellmouth-shaped portion presses itself againstthe internal surface of the small-diameter tapered portion,

thereby making possible very easy and speedy assemblage.

Further, the electrical connector according to the present inventioncomprises at least one terminal including a male or female Contact atone end thereof, a resilient bellmouth portion in the midway thereof,and at least one protrusion or groove formed along the periphery of thebellmouth portion; and a connector body including at least oneterminal-receiving aperture with an internal surface partially or whollytapered, the tapered portion having at least one groove or protrusionadapted to engage with the protrusion or groove on the periphery of thebellmouth portion. The terminal is inserted into the tapered portionfrom its large-diameter side to such an extend that the protrusion orgroove on the terminal comes to engage with the groove or protrusion onon the tapered portion, whereby the protrusion or groove formed on theperiphery of the terminal is held by the groove or protrusion on thetapered portion, at the same time the bellmouth portion beingresiliently pressed against the internal surface of the tapered portion.

For the electrical connector according to the invention to work, it isenough to insert the terminal into the terminal-receiving aperture fromthe large-diameter side of the tapered portion to such an extent thatthe groove or protrusion on the bellmouth-shaped portion of the terminalcomes to engage with the protrusion or groove formed on the internalsurface of the tapered portion, and therefore the electrical connectoraccording to the invention can be assembled very easily and quickly.

In order to achieve the second object of the invention, namely, toprovide an electrical connector in which the inserted terminal iscombined firmly with the connector body in such a manner as to alwaysmaintain its center line aligned with that of the mating terminal, theelectrical connector according to the invention has an almost tubularbody with a narrow gap which is extended longitudinally from end to endand the resilient hook is formed sideway from the bellmouth-shapedportion of the terminal. Further, at least two longitudinal custs areprovided on the bellmouth-shaped portion of the terminal and at leastone resilient protrusion is formed by pushing sideway the portionbetween the Cuts.

The terminal is generally made of such materials as copper, copperalloys, aluminum or aluminim alloys, and the connector body of suchmaterials as hard rubher or plastics. But it is needless to say that thematerials employed are not limited to the above-mentioned ones. In otherwords, anymaterial with a desired electrical conductivity and mechanicalstrength may be used for the terminal, and as to the material of theconnector body, the only Conditions to be met are satisfactory degree ofelectrical insulation and mechanical strength.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a diagram showing an exampleof the male terminal employed in the electrical connector according tothe present invention.

FIG. 2 is a diagram for explaining the back side of the male terminalshown in FIG. 1.

FIG. 3 is a partially exploded view showing an example of the electricalconnector according to the present 3 invention assembled employing themale terminals shown in FIGS. 1 and 2.

FIG. 4 is a diagram showing another embodiment of the male terminalemployed in the electrical connector according to the invention.

FIG. 5 is a rear view showing the male terminal of FIG. 4.

FIG. 6 is a partiallyexploded sectional view showing another embodimentof the electrical connector according to the invention which has beenassembled using the male terminal shown in FIGS. 4 and 5.

FIG. 7 is a sectional view taken in the line VII VII in FIG. 6.

FIG. 8 is a diagram showing still another embodiment of the maleterminal used in' the electrical connector according to the invention.

DESCRIPION OF THE PREFERRED EMBODIMENTS Embodiments of the inventionwill be now explained with reference to the attached drawings.

Referring to FIGS. 1 to 3, a male terminal 1 is formed by press-moldinga sheet of tin-coated copper alloy plate. More in detail, the maleterminal is provided with a contact portion of the male type at one endthereof, a resilient beIlmouth-shaped portion 3 in the midway thereof,and at least one resilient hook 4 extending sideway from thesmall-diameter side or the front side of the bellmouth-shaped portion.

In the embodiment shown above, resiliency of the bellmouth-shapedportion is provided by the gap 6 between the edges 5, the resilientmaterial of the terminal and at least one resilient finger 7 cut uptoward the reader as shown in FIG. 2. The hook 4 is also cut up in sameway as the finger 7.

The terminal has also clamps 11 and 12 formed on it to hold theconductor 9 of an insulated lead wire 8 and an insulating covering 10. i

The reference numeral 13 shows a connector body of molded hard plastics,which is internally provided with a terminal-receiving aperture 14 witha tapered smalldiameter portion 15.

As is apparent from the drawings, the terminal is inserted into theterminal-receiving aperture 14 of the connector body 13 from itsrighthand side, as shown in FIG. 3, to such an extent that the hook 4 ofthe terminal 1 which enters the aperture 14 from the large-diameter sideof the tapered portion 15 reaches beyond the smallest-diameter sidethereof.

The hook 4 is arranged to the axial line of the terminal l in accordancewith the contour of the internal surface of the tapered portion 15 aspassing through it, and after having passed the tapered portion 15, thehook 4 of the terminal 1 is restored to its original position by its ownresiliency thereby to engage with the holding portion 16 around thesmallest-diameter side of the tapered portion 15.

The resilient beIlmouth-shaped portion 3 is deformed by being pressedagainst the internal surface of the tapered portion 15 of the connectorbody 13 by the excessive insertion of the terminal 1, thereby applyingrestitutory force to the internal surface of the tapered portion 15.

Althougn only the male terminal has been taken up by way of example forexplanation in the preceding embodiment, female terminals are alsoconstructed almost in the same way. FIG. 3 also shows an embodiment ofthe electrical connector according to the present invention involvingfemale terminals. As can be seen from the figure, the female terminalsare constructed the same way as the already-mentioned male terminalsexcepting the contact of female type 102 formed at one end of theterminal 101. It is also needless to say that the female terminal 101 isinserted from the lefthand side of the terminal-receiving aperture 114of a connector body 113 made of the same plastic material as theconnector body 13 by molding.

When the male and female connectors and 200 respectively of theabove-described construction are connected with each other by insertingthe male electrical connector 100 into the receiving aperture 114 of thefemale electrical connector 200, as shown in FIG. 3, the male contact 2is at the same time inserted with pressure into the female contact 102,thereby accomplishing electrical connection between them.

It will be understood from the above description that the presentinvention uses the hook 4 which engages with the holding portion 16formed inside the connector body 13 and the portion 3 of the terminal 1is pressed against the internal surface of the tapered portion 15,resulting in the terminal 1 and the connector body 13 being connected orengaged with each other very strongly in the axial direction. As aresult, it is absolutely impossible that the terminals come off from theconnector body 13 at the time of connection or disconnection of theelectrical connector 13. In addition, since the bellmouth-shaped portion3 of the terminal 1 is maintained pressed against the tapered portion 15resiliently, the axial line of the terminal is always maintained in thesame position, thereby eliminating the inability of the terminal 1 toengage with the mating terminal 101 which otherwise might occur at thetime of insertion due to the out-of-alignment condition of the axiallines of the terminals.

In assembling the electrical connector according to the invention, theterminal 1 is inserted into ther terminal-receiving aperture 14 from thelarge-diameter side of the tapered portion 15 to such an extent that thehook 4 of the terminal 1 go past the smallest-diameter side of thetapered portion 15, whereupon the hook returns to its original positionby its resiliency and automatically engages with the holding portion 16,while the bellmouth-shaped portion 3 is pressed against the taperedinternal surface of the connector body, making the assembly work verysimple and speedy.

Referring now to FIGS. 4 to 7 showing another embodiment of theelectrical connector according to the invention, a male terminal 201,like the one shown in the preceding embodiment, is formed bypress-molding a sheet of tin-coated copper alloy plate. More in detail,the present embodiment comprises a male contact 202 at one end thereof,a resilient bellmouth-shaped portion 203 in the midway thereof and atleast one groove 204 formed along the periphery of the bellmouthshapedportion 203.

In this embodiment, like the preceding one, the resiliency of thebellmouth-shaped portion 203 is supplied by the presence of the gap 206between a pair of the edges 205 and the resilient material of theterminal. Also, the terminal 201 is the same as the one in the precedingembodiment in that the clamps 211 and 212 support the conductor 209 ofan insulated lead wire 208 and an insulating covering 210.

The connector body 213 which is made of the same plastic material as theconnector body 13 of the preceding embodiment by molding has a taperedinternal surface and a terminal-receiving aperture 214 having in themidway thereof a tapered portion 215 provided with at least one integralprotrusion 216 occupying a peripheral portion of the internal surface.

As will be understood from the drawing, the terminal 201 is insertedinto the terminal-receiving aperture 214 of the connector body 213 fromthe right-hand side thereof to such a depth thatthe protrusion 216 onthe internal peripheral surface of the tapered portion 215 engages withthe groove 204 along the periphery of the bellmouth-shaped portion 203of the terminal 201.

As a consequence, the bellmouth-shaped portion 203 which had beendeformed toward the axial line of the terminal by the protrusion 216 onthe internal peripheral surface of the tapered portion 215 is pressedagainst the internal surfzce of the tapered portion 215 at the same timethat the protrusion 216 engages with the groove 204.

The above explanation was made employing the male terminal, but theconstruction of the female terminal is almost the same as that of themale terminal. FIG. 6 also shows an example of the female terminal, thefemale terminal is constructed the same way as the male terminal exceptthe fact that a female contact 302 is formed at one end of the terminal301.

In the electrical connector of the above construction, the protrusion216 formed on the internal surface of thetapered portion 215 of theconnector body 213 engages with the groove 204 on the periphery of thebellmouth-shaped portion 203 of the terminal 201, while at the same timethe bellmouth-shaped portion 203 is pressed against the internal wall ofthe tapered portion 215 by means of resilient force applied in theradial direction. Therefore, the terminal 201 and the connector body 213are engaged or combined with each other very strongly in the axialdirection, with the result that it never happens that the terminal comesoff from the connector body 213 when the electrical connectors areconnected or disconnected. Further, the fact that the bellmouth-shapedportion 203 of the terminal 201 is resiliently maintained pressed incontact with the internal surface of the tapered portions 215 results inthe axial line of the terminal 201 being maintained in position, thuseliminating the case in which the terminal is incapable of engaging withthe mating terminal due to the out-of-alignment condition of the axiallines of the terminals.

Also, the assembly work of the electrical connector is easily performedsimply by inserting the terminal 201 into the terminal-receivingaperture 214 from the large-diameter side of the tapered portions 215until the protrusion 216 formed on the internal wall of the taperedportion 215 engages with the groove 204 in the bellmouth-shaped portion203 of the terminal 201.

In the above explanation in connection with FIGS. 4 to 7, it isdescribed that the terminal has the groove in its bellmouth-shapedportion and the protrusion is provided on the internal wall of thetapered portion of the terminal-receiving aperture. On the contrary,however,

the terminal may have such a protrusion in its bellmouth-shaped portionand the internal wall of the tapered portion may be provided with such agroove. It is clear that such an alternative construction delivers thesame effect as that shown in FIGS. 4 to 7.

Still another embodiment of the male terminal is shown in FIG. 8. Thisembodiment has the same construction as that shown in FIGS. 1 to 3, theonly difference being that in the embodiment of FIG. 8 the resiliency ofthe bellmouth-shaped portion 403 is derived solely by a cut-upprotrusion 418..

As is clear from the above explanation, the present invention providesan electrical connector with a very high industrial and commercial valuein which the terminal is fitted in the connector body very easily andthe terminal, once fitted, engages strongly with the connector body insuch a manner as to maintain the axial line thereof in position formutual engagement with the mating terminal. I

We claim:

1. An electrical connector comprising at least one terminal having asubstantially tubular shape with a narrow gap extending longitudinallyfrom one end to the other end thereof, said at least one terminalincluding a contact portion at one end, a resilient bellmouthshapedportion formed at a middle portion and at least one resilient hookpositioned at a smaller-diameter side of said bellmouth-shaped portion,said at least one hook projecting radially from said bellmouth-shapedportion; and a connector body including at least one internal bore forreceiving said terminal, said at least one bore having a tapered portionwith a circular crosssection on at least a part of the internal surfaceof the bore, said tapered portion decreasing in diameter uniformly inthe radial direction along its axis from a larger-diameter end and aholding portion disposed at a smaller-diameter end of said taperedportion, said terminal being inserted into said here from thelargerdiameter end of said tapered portion to such an extent that saidhook passes said smaller-diameter end of said tapered portion, such thatsaid hook is held by said holding portion and said bellmouth shapedportion is resiliently pressed in a surface contact against the internalsurface of said tapered portion.

2. An electrical connector according to claim 1, wherein said contactportion includes one of a male contact portion and a female contactportion.

3. An electrical connector according to claim 1, wherein said at leastone resilient hook is formed of a resilient finger having one endextending outwardly from said bellmouth-shaped portion.

4. An electrical connector according to claim 1,

wherein at least one resilient finger extending outwardly .from alarger-diameter side of said bellmouthshaped portion is provided toobtain resilient contact with the internal surface of said taperedportion.

5. An electrical connector according to claim 1,

wherein at least one protrusion is formed on said bellmouth-shapedportion to provide resilient contact with the internal surface of saidtapered portion.

1. An electrical connector comprising at least one terminal having asubstantially tubular shape with a narrow gap extending longitudinallyfrom one end to the other end thereof, said at least one terminalincluding a contact portion at one end, a resilient bellmouth-shapedportion formed at a middle portion and at least one resilient hookpositioned at a smaller-diameter side of said bellmouth-shaped portion,said at least one hook projecting radially from said bellmouth-shapedportion; and a connector body including at least one internal bore forreceiving said terminal, said at least one bore having a tapered portionwith a circular cross-section on at least a part of the internal surfaceof the bore, said tapered portion decreasing in diameter uniformly inthe radial direction along its axis from a largerdiameter end and aholding portion disposed at a smaller-diameter end of said taperedportion, said terminal being inserteD into said bore from thelarger-diameter end of said tapered portion to such an extent that saidhook passes said smaller-diameter end of said tapered portion, such thatsaid hook is held by said holding portion and said bellmouth shapedportion is resiliently pressed in a surface contact against the internalsurface of said tapered portion.
 2. An electrical connector according toclaim 1, wherein said contact portion includes one of a male contactportion and a female contact portion.
 3. An electrical connectoraccording to claim 1, wherein said at least one resilient hook is formedof a resilient finger having one end extending outwardly from saidbellmouth-shaped portion.
 4. An electrical connector according to claim1, wherein at least one resilient finger extending outwardly from alarger-diameter side of said bellmouth-shaped portion is provided toobtain resilient contact with the internal surface of said taperedportion.
 5. An electrical connector according to claim 1, wherein atleast one protrusion is formed on said bellmouth-shaped portion toprovide resilient contact with the internal surface of said taperedportion.